Be sure to click 'more' and select 'suggest as answer'!
If you're the thread creator, be sure to click 'more' then 'Verify as Answer'!
Reviewed tutorial "Explore Working Applications of 8 Different Op-Amp Circuits" (https://www.youtube.com/watch?v=aR9ILhbG4AE&t=317s)
@12:14 he indicates turning on the Reference Voltage which drives the opAmps input. Is this Reference Voltage a voltage divider connected to Non-Inverting input (pin 3)?
I had a bit of time, and decided to try to simulate that circuit.
If you wish to run it, the steps are:
(1) Install KiCad 10
(2) Unzip the summing_amp_demo zip file somewhere
(3) Use File->Open Project in KiCad, and then click on the Schematic Editor icon to see the circuit. In this screenshot, you can see on the left side that the op-amp is being powered from +-15V, and that one input is a sinewave, and the other is a 0V DC level.
(4) Click on Inspect->Simulate, and then click on the blue triangle to run the simulation, and you'll see this chart. The colors are labeled on the right side.
(5) Now if you change the DC level from 0V to any other value (say) 1V, and re-click the blue triangle, you'll see the change in the output.
I had a bit of time, and decided to try to simulate that circuit.
If you wish to run it, the steps are:
(1) Install KiCad 10
(2) Unzip the summing_amp_demo zip file somewhere
(3) Use File->Open Project in KiCad, and then click on the Schematic Editor icon to see the circuit. In this screenshot, you can see on the left side that the op-amp is being powered from +-15V, and that one input is a sinewave, and the other is a 0V DC level.
(4) Click on Inspect->Simulate, and then click on the blue triangle to run the simulation, and you'll see this chart. The colors are labeled on the right side.
(5) Now if you change the DC level from 0V to any other value (say) 1V, and re-click the blue triangle, you'll see the change in the output.
Hi @shabez, I guess I am still confused how his circuit is constructed. Input 1 has a Pot, Input 2 is a since wave. When he said in the video he turns on the reference voltage @12:15. There he adjusts the Pot to move the output up and down? So the 2nd diagram I was assuming the voltage divider would be also connected to the inverting terminal. Otherwise where is he connecting the reference voltage along with the Pot when he says turning it on ?
Yes I do use kiCad. I had lots of issues finding the correct spice models for opamps. That's why i was a little hesitant on trying the simulation. But, that's great you have done this to make things easier to understand. Works as expected. I modified input2 to incorporate a sine wave and Pot. Please verify if this makes sense. Thankx so much. BTW, how do you add a zip file? Don't see any option under Insert pulldown other than image/video file.
Just noticed the potentiometer. You've connected it correctly in KiCad, however that symbol doesn't simulate, it may generate an error. You can replace it with a different symbol (see the screenshot below) called Potentiometer but it has to be the one which is in the Simulation_SPICE symbol library.
When you do that, you'll be able to set the position of the control by double-clicking on it or the text, and changing the "pos=" value to anything between 0.0 and 1.0. I can't recall if 0.0 is leftmost or rightmost unfortunately, so you'll have to look out for that.
